546 
Diseases  of  Cattle  and  Sheep. 
mine,  well  acquainted  with  their  present  method  of  management, 
says,  “The  Highland  farmers  manage  these  things  better  now 
than  formerly.  Both  hay  and  roots  are  provided,  and  rough 
shelter  occasionally  afforded  in  inclement  weather.  Thev  have 
been  taught  by  sad  experience,”  he  says,  “ the  lesson  which 
Liebig  first  promulgated  in  theory,  that  food  in  sufficient  quan- 
tities is  not  only  requisite  to  supply  the  waste  and  growth  of  the 
body,  but  for  producing  animal  heat  : and  the  more  the  cattle  or 
sheep  are  exposed  to  cold,  the  greater  is  the  quantity  of  food 
required  to  preserve  their  condition  and  health.  Hence  shelter 
is  an  equivalent  for  food.” 
But,  confining  our  attention  more  particularly  to  the  effect  of 
cold  and  wet  on  the  farmer’s  live  stock  in  English  agricultural 
districts. 
First,  with  respect  to  sheep.  These  animals  are  able  to  bear 
both  severe  cold  and  wet,  when  they  are  sufficiently  fed.  It  is 
this  which  preserves  them  under  many  a difficulty.  Witness  a 
flock  of  hogs  folded  on  turnips  midst  snows  and  frosts  and  rain. 
Their  natural  dispositions  are  at  war  with  such  a system  ; but  by 
the  use  of  artificial  food,  such  as  linseed-cake  or  corn,  they  are 
rendered  capable  of  withstanding  these  influences. 
I have  been  accustomed  to  see  much  mismanagement  of  sheep 
with  respect  to  insufficiency  of  food.  I allude  to  the  Leicester 
breed  chiefly.  They  have  great  tendency  to  fatten,  and  quickly 
acquire  flesh;  but  they  are  less  able  to  bear  exposure  to  cold  in 
the  absence  of  proper  food  than  the  South  Downs.  The  Leicester 
sheep  have  greater  development  of  lax  extensible  cellular  tissue 
in  the  soft  solids — their  vascular  and  nervous  systems  are  also 
more  sluggish  and  inactive.  These  are  points  indicating  tempe- 
raments of  a lower  degree  of  vital  energy,  and  hence  their  consti- 
tutions are  more  easily  acted  on  by  these  physical  agents.  In 
the  absence  of  sufficient  and  proper  food  their  wool  becomes 
short,  inelastic,  and  brittle,  and  the  yolk  is  insufficiently  secreted. 
In  this  weak  and  inefficient  state  the  wool  affords  very  little  pro- 
tection during  wet  and  stormy  weather ; for,  instead  of  throwing 
off  the  rain,  which  it  will  do  when  preserved  in  its  integrity,  it 
rather  retains  it,  and  this,  acting  as  a chill,  checks  external  secre- 
tion, constricts  and  obstructs  the  vessels  of  the  surface,  and  the 
greater  mass  of  blood  is  then  thrown  in  undue  proportions  upon 
the  internal  organs,  causing  congestions  of  the  mucous  membranes 
of  the  alimentary  canal  and  of  the  air-passages,  inducing  fluxes: 
here  is  the  common  cause  of  diarrhoea  amongst  lambs  in  the 
spring  season  when  the  ewes  have  been  neglected  in  the  winter, 
and  rendered  thereby  incapable  of  supplying  them  with  sufficient 
milk.  Hence  also  we  have  diarrhoea,  and  catarrh  with  nasal  flux 
amongst  the  hog-sheep  in  the  winter  and  early  spring. 
